Luxman SQ-30u noise

I just replaced stock tubes with vintage tubes. I started hearing static/crackling/hiss in both channels. Noise increases and decreases in volume, and sometime disappears entirely, but always returns. Does not change with volume setting (same at min and max volume). Does not change between phono or CD selection. Not noticeable when playing through speakers, but, somewhat distracting with headphones. Overall, I think the sound is enhanced with the replacements.

Noise obviously resulted from tube switch. Since I know nothing about electronics, is it more likely the power tubes or EC82/EC83s are the problem? I really don't want to put the no name tubes back in. Or should I replace 1 at a time to find the noisy offender(s)? Thanks in advance.

More info. Turns out the noise is in one channel only. The noise sounds similar to noise you get between songs on a less than mint vinyl Lp.
Just to be sure, I would put the old tubes back in and make sure that everything returns to normal.
I put the old tubes back with no change. Another observation. I hear the noise in the headphones (one channel only)) even when nothing is hooked to the amp. It does not matter what settings I have on the amp.
You may have a dirty or intermittent tube socket on the noisy channel.